Housings for receiving printed circuit boards equipped with components are known in various embodiments. With a housing which is used for termination units of a communication system there is frequently the demand for the basic structural design to be able to be expanded for different terminals. A telecommunications device can for example be arranged in its basic design for two S0 exchange ports and four analog subscriber lines. In an expanded capacity stage the system should be able to be expanded for further system terminations. The housing is expanded by fitting additional analog and/or digital subscriber interfaces in the form of extension cards which are connected by means of plug-in devices to the main printed circuit board of the communication system. This means that space must be provided within the housing for these extension cards which must be accessible to authorized persons but not accessible to the user. On the other hand a connection area must be provided in the housing which is easy to open for the user, to enable his subscriber termination units to be connected to the communication system.
Termination units of a telecommunications system are manufactured in high volumes and the housing must be as simple and as cheap as possible to manufacture.